Vent plug



HET'ULD May 15, 1945. H. A. COHEN VENT PLUG Filed Sept. 8, i942 l ll/ IIIIIIII/ IIIIIIII/ I'Illll/ III! A Patented May 15, 1945 v N'r PLUG Harold Arthur-Cohen, Kingston, ntario, Canada ApplicationSeptember 8, 1942,'Serial No. 4575683 in-Canada September 10, :1941

This invention relates to non-spill vent plugs for liquidcontaining receptacles such as "storage batteries and the '-like.' Vent plugs of this type are used in storage batteries to-allow the gases which are generated inthebattery-to escape into the atmosphere and to prevent "the 'li quid'electrolyte frcmescaping shouldthebattery be tilted I or inverted.

Various types-of valveshave been "provided in vent plugs "for this purpose usually involving "a movable member and a valve seat but these have proven unreliable since it is diliicult to provide a Eleak-proof valve of this type in view -of-"corrosion and *for other reasons; Flexible diaphragms havebeen used in a valve action-but it is necessary to make the diaphragm quite delicate and as a "result it soon becomes stretched and loses its sealing ability. Flexible tubes have "also been provided invent plugs -with-mean-s for kinking or closing the tube upon inversion of the battery.

'Ihis'type of valve is not leak-proof since it is-necessary to provide a plurality jof-bafiie plates and chambers to collect the liquid electrolyte.

Accordingly it is the-mainobject of'the pres ent invention to provide a non-spillvent .plugfor liquid :containing receptacles which will :allow gases to; escape into the atmosphere whenthe receptacle is :in normal position and awhich'mill prevent the liquid fromescaping should thereceptacle be tilted or inverted. It is also ranobject of the present invention to provide a vent plug which-will be neliablygileak-pnoof :andwhich will retain its sealing ability for arlongpericd.

In accordance with the present invention :a'

closed flexible tube is provided communicating with the usual aperture in-the cover portion of the vent plug. This tube hasa plurality .ofcircumferentially cut slits' which are :heldppen when the receptaclefis in normal position and I and the flexible tube are mounted within a casing I which isattached to the 'cover portion of the vent plug and which is provided with a plurality of apertures communicating with the interior of the receptacle. In a modification of the invention the weight comprises a metal, ball which is free to roll within a cage member which is attached to the lower end of the flexible tube and which is adapted to travel in suitable slots in the casing. Elna 'further modiflca'tion the weight comprises a metal ball which is adapted to rest on a -plunger member when the receptacle is in normal position-and'to rol1'c1ear of the plunger member WllBll the receptacle is tfltedor inverted, the plunger member passing through the flexible tube and being attached to the lower end thereof. .In this modification the slits will"close by 13118 force of velasticity :of the flexible tube. ina "furtherimodificationa second metal ball is 'provided below the flexible tube to aidin the :closing of the, islits when the :receptacleisinverted. The second metal "ball -andrthe tube are mounted 'withina w-terior of thenreceptacla,

.Furtherobjects and. advantages :of thespresent invention will :be apparent upon reference tothe end of the flexible tube and the weight member accompanying drawing which illustrates the invention as applied to a storage battery.

I Fig. .1.is a vertical :sectionalview .of .a storage batteryshowing the-construction .of the vent plug.

, I Fig-2 is an enlarged view of part-of the :flexible tube and weight membershowing the circumferential slit inopenposition. i

Rig. .3 lean-enlarged viewoi part of the casing. Fig. 4 is a verticalisectional view ofa modification .of the invention.

, Fig. 5115 a vertical sectional view of a further modification of the invention. I

. 'Fig. 16 is a vertical sectional view of a further modification and "Fi '7 is a sectional view taken on the line -'l-.- I

.cf Fig. 6.. I II I The storagebattery illustrated comprises the usual receptacle In, cell cover ll, positive and negative plates l2 and positive and negativeposts 3. Each cell cover is provided with :a flanged opening into which a vent plug is adapted toihe screwed. I

The vent plughas .acover portion IA-having an aperture 15 therein.j A closed flexible .itube I8 communicates with'this aperture and is provided With a vplurality?of.1c'ircijinferentially cut slit openings 11. A single slit'would be suflicient but it is preferable that the tube be provided with a I slit on opposite sides thereof. Referring to Fig. 1

a weight member I8 is attached to the lower end of the flexible tube and the weight'member and tube are mounted within a casing I9 which is at-.

tached to the cover portion l4 and which is provided with a plurality of apertures 20 communieating with the interior of the receptacle. The

usual gasket 2| is provided between the vent plug and the flange of the cell cover. When the storlyte will pass through the apertures 20 into the.

casing l9 but will be prevented from escaping further because the slits I! will be closed by the force of elasticity of the flexible tube and by the force of gravity of the weight member.

Referring to Figs. 6 and '7 the weightmember comprises a metal ball 22 which isfree to roll within a cage member 23. This cage member is attached to the lower end of the flexible'tube, the cage member and the flexible tube being mounted within the casing IS. The casing is provided with suitable slots 24 in which the cage member travels. Mounting the metal ball in a cage reduces friction and increases the sensitivity of the device.

In the vent plugs shown in Figs. 4 and 5 there is room in the cover portion It for a metal ball 25 to roll freely. When the receptacle is in normal position the ball will rest on a plunger member 26, the shaft of which passes through the flexible tube l6 and is attached to the lower end thereof as at 27. When the receptacle is in normal position the force of gravity of the metal ball on the plunger member holds the slits I! open. When the receptacle is tilted or inverted the metal ball will roll clear of the plunger member and the slits will be closed by the force of elasticity of the flexible tube. In Fig. 4 a second metal ball 28 is provided below the flexible tube to aid in the closing of the slits. The flexible tube and the second weight are mounted within the casing H! which is. attached to the cover portion and which is provided with a plurality of apertures communicating with the interior of the receptacle. In this modification the slits will be closed by the combined force of elasticity of the tube and force of gravity of the weight member 28.

The weight members mentioned above are preferably composed of lead so that they will not be subject to corrosion. The casings have been described as having a plurality of apertures but it is to be understood that a single aperture would operate quite satisfactorily.

Accordingly I have provided a novel non-spill vent plug for liquid containing receptacles which will allow gases to escape into the atmosphere when the receptacle is in normal position and which will prevent the liquid from escaping should the receptacle be tilted or inverted.

I claim:

1. A non-spill vent plug for a liquid containing receptacle, comprising a cover portion having an perture therein, a closed flexible tube communicating with said aperture and provided with "in which the weight member comprises a cage least one slit opening, a, weight member for holding said slit open when the receptacle is in normal position and for assisting to hold the slit closed when the receptacle is inverted.

5. A non-spill vent plug for a liquid containing receptacle, comprising a cover portion having an aperture therein, a closed flexible tube communicating with said aperture and provided with at least one circumferential slit opening, a weight member acting on the lower end of the tube and tending to stretch said tube when the receptacle is in the normal position and thereby hold the slit open and means for relieving the tube of the action of the weight member when the receptacle is tilted.

6. A non-spill vent plug according to claim 5, comprising a plunger member passing through the flexible tube and attached to the lower end thereof and in which the weight member comprises a metal ball adapted to rest on the upper end of said plunger member when the receptacle is in normal position and to roll clear of said member when the receptacle is tilted or inverted.

7. A non-spill vent plug according to claim 4, in which the slit opening is held open by one weight member and is held closed by a second weight member and the force of elasticity of the flexible tube.

8. A non-spill vent plug according to claim 5, comprising a plunger member passing through the flexible tube and attached tothe lower end thereof and in which the weight member comprises a metal ball adapted to rest on the upper end of said plunger member when the receptacle is in normal position and to roll clear of said member when the receptacle is tilted or inverted, and comprising acasing for the flexible tube having apertures communicating with the interior of the receptacle and a second metal ball free to move in said casing adapted to exert pressure on the normally lower end of the flexible tube when said receptacle is inverted. 

